Regex:

require ["regex","variables"];

if header :contains "from" "activate.de" {
	if header :regex "from" "@(.*).activate.de" {
		fileinto "INBOX.activate.${1}";
	}
}

Flags:

require ["imap4flags"];

if header :contains "subject" "package update" {
	addflag "$label4";
}

Flags und "eigener" Header:

if header :contains "List-Id" "hotfix.lists.activate.de" {
	# Als gelesen markieren
	setflag "\\Seen";
	fileinto "INBOX.Hotfix";
	# Bearbeitung beenden
	stop;
}